Device for preventing deflection of elongated workpieces

ABSTRACT

A device for preventing deflection of an elongated workpiece rotating about its longitudinal axis is provided with a contact ring (9) that is rotatably mounted about a support shaft (12) perpendicular to the axis of rotation of the contact ring (9). The angle of inclination of the rotational axis of the contact ring (9) is variable relative to the rotational axis of the elongated workpiece (M) inserted throught the ring (9), by rotating the housing (6) about the support shaft (12). The periphery of the workpiece (M) is supported by the inner periphery of the contact ring (9) at two points, i.e., at axial ends of the contact ring. Thus, elongated workpieces of different diameters can be supported by varying the inclination angle of the axis of the contact ring (9) relative to the workpiece (M).

TECHNICAL FIELD

The present invention relates to a device for preventing the deflectionof elongated workpieces rotating about their longitudinal axis.

BACKGROUND ART

Elongated workpieces are machined by apparatus such as lathes, whilebeing rotated about their longitudinal axis. If the workpiecedeflectively revolves in this case, problems such as reduced machiningaccuracy and a break in the cutting tool will arise.

FIG. 11 shows a device for preventing the deflection of an elongatedworkpiece rotating about its longitudinal axis. This device comprises aplurality of bolts 31 screwed through a frame 30 around the elongatedworkpiece M, and a contact member 32 attached to the forward end of eachbolt 31. The bolts are moved inwardly or outwardly of the frame 30 inaccordance with the outside diameter of the workpiece M to cause thecontact members 32 to support the outer periphery of the workpiece Magainst deflection.

With the deflection preventing device shown in FIG. 11, however, theelongated workpiece M is supported at only one point along its length,therefore greatly deflectively revolves in front and rear of thesupported position as seen in FIG. 10 and can not be prevented fromdeflection fully effectively. When some kinds of elongated workpieces Mwhich are different in outside diameter are to be supported by thedevice, the plurality of bolts 31 must be rotated individually to adjustthe amount of projection of each bolt into the frame 30, hence a verycumbersome adjusting procedure.

An object of the present invention is to overcome the foregoingdrawbacks of the prior art.

DISCLOSURE OF THE INVENTION

The present invention provides a device for preventing deflection of anelongated workpiece M rotating about its longitudinal axis, the devicebeing characterized in that it comprises a housing 6, and a contact ring9 rotatably mounted on the housing 6 for inserting the elongatedworkpiece M therethrough, the housing 6 being rotatable about a supportshaft 12, the support shaft 12 being perpendicular to the axis ofrotation of the contact ring 9, the angle of inclination of therotational axis of the elongated workpiece M relative to the axis ofrotation of the contact ring 9 being variable by the rotation of thehousing 6 about the support shaft 12, the outer periphery of theelongated workpiece M being supportable by the inner periphery of thecontact ring 9 at its axial one end and at the other end thereof.

Thus, the elongated workpiece M is supported by two points, i.e., oneend and the other end of the inner periphery of the contact ring 9, withthe result that the deflective revolution of the workpiece M is smalleras seen in FIG. 9 than is the case with FIG. 10. Further when aplurality of kinds of elongated workpieces M different in outsidediameter are to be supported, the angle of inclination of the rotationalaxis of the contact ring 9 is variable relative to the rotational axisof the workpiece M by rotating the housing 6 about the support shaft 12,whereby the contact ring 9 is adapted to support each of the workpiecesM of different outside diameters with one end and the other end of itsinner periphery.

Preferably, the housing 6 is in the form of a hollow cylinder, and thecontact ring 9 is fitted in the cylindrical housing 6, whereby thecontact ring 9 can be held in place with good stability.

Preferably, a bearing 7 is interposed between the housing 6 and thecontact ring 9. This renders the contact ring 9 smoothly rotatable.

The elongated workpiece M can be prevented from defacement by preparingthe contact ring 9 from a material other than the metal.

The contact ring 9 may be in the form of an integral piece or maycomprise two divided segments as arranged side by side axially of thering.

The angle of rotation of the housing 6 about the support shaft 12 can beadjusted promptly by adjusting means 17 therefor for elongatedworkpieces M of different outside diameters.

When equipped with drive means 16 for rotating the housing about thesupport shaft 12, the device is usable also for machining apparatuswhich are operable without any operator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 4 show a deflection preventing device as a first embodimentof the invention;

FIG. 1 is a front view of the device;

FIG. 2 is a view in section taken along the line A--A in FIG. 1;

FIG. 3 is a perspective view of a stopper ring;

FIG. 4 is a perspective view of the device in use;

FIGS. 5 to 8 show another deflection preventing device as a secondembodiment of the invention;

FIG. 5 is a front view of the device;

FIG. 6 is a view in section taken along the line B--B in FIG. 5;

FIGS. 7 and 8 are sectional views showing the device in different statesduring use;

FIG. 9 is a diagram illustrating the principle of the invention;

FIG. 10 is a diagram illustrating the principle of the prior art; and

FIG. 11 is a front view of a conventional deflection preventing device.

BEST MODE OF CARRYING OUT THE INVENTION

A first embodiment of the invention will be described with reference toFIGS. 1 to 4.

FIG. 4 shows a device 2 for preventing deflection of the elongatedworkpiece M to be machined by a machining apparatus 1. The machiningapparatus 1 has a support block 3 for supporting an intermediate portionof the elongated workpiece M and rotates the workpiece M about itslongitudinal axis. A feeder 4 also supports the workpiece M at its oneend and feeds the workpiece axially thereof to the machiningapparatus 1. The elongated workpiece M thus rotated about itslongitudinal axis and fed axially thereof is cut to the desiredconfiguration by a cutting tool 5.

Between the machining apparatus 1 and the feeder 4, the elongatedworkpiece M is prevented from deflective revolution by the deflectionpreventing device 2.

With reference to FIGS. 1 and 2, the device 2 comprises a housing 6 inthe form of a hollow cylinder, and a ring holder 8 in the form of ahollow cylinder and rotatably mounted by a bearing 7 on the housing 6. Acontact ring 9 made of resin is held by the ring holder 8. The elongatedworkpiece M is inserted through the contact ring 9.

With the present embodiment, the contact ring 9 is divided into a firstring 9a at one axial end of the ring 9 and a second ring 9b at the axialother end thereof. An annular cutout 10 is formed in one end face ofeach of the first ring 9a and the second ring 9b. An annular spring 11is fitted around the radially inner portion defining the cutout 10. Eachof the first ring 9a and the second ring 9b is integrally formed with acontact portion 9c V-shaped in cross section and projecting from thering inner periphery radially inwardly thereof.

A support shaft 12 extends outward from the outer periphery of thehousing 6 perpendicular to the axis of rotation of the contact ring 9.The support shaft 12 is rotatably supported by a mount bracket 13.Support brackets 14 and a support rod 15 are connected to the mountbracket 13 as seen in FIG. 4. The support rod 15 is attached to themachining apparatus 1. The housing 6 is rotatable about the supportshaft 12.

Also attached to the mount bracket 14 is a hydraulic cylinder 16, bywhich the housing 6 is drivingly rotatable about the support shaft 12.The support shaft 12 is projected from the hydraulic cylinder 16, andthe projection 12a is in the form of a rod of square cross section so asto be engageable by a tool such as a spanner. The housing 6 is rotatablealso manually.

The mount bracket 14 is further provided with means 17 for adjusting theangle of rotation of the housing 6 about the support shaft 12. Theadjusting means comprises a stopper ring 19 fitted around a hollowcylinder 18 projecting from the mount bracket 13 toward the housing 6and concentric with the shaft 12. As shown in FIGS. 2 and 3, the stopperring 19 has a divided portion, and lugs 20, 21 extend from therespective divided ends radially outwardly of the ring. The stopper ring19 is fixedly fastened to the cylinder 18 by interconnecting the twolugs 20, 21 with a bolt 22. The lug 20 is integral with an engagingpiece 23 extending therefrom toward the housing 6. The housing 6 is inengagement with the engaging piece 23, whereby the angle of rotation ofthe housing 6 about the support shaft is determined as specified asindicated in phantom line in FIG. 2. The angle of rotation of thehousing 6 about the shaft 12 is adjustable by rotating the stopper ring19 relative to the cylinder 18 and shifting the engaging piece 23circumferentially of the cylinder.

The elongated workpiece M can be prevented from deflective revolution bythe device 2 by inserting the workpiece M through the contact ring 9,rotating the housing 6 about the support shaft 12 and thereby causingthe outer periphery of the workpiece M to be supported at two positions,i.e., by the inner periphery of the first ring 9a and the innerperiphery of the second ring 9b as indicated in phantom line in FIG. 2.The deflection of thw workpiece M can be diminished by supporting theworkpiece M at the two points in this way. The contact ring 9 is notmade of metal and therefore will not deface the workpiece M whilesupporting the workpiece. The contact ring 9 may be made of a softmetal.

Although the housing 6 may be rotated manually about the support shaft12, the use of the hydraulic cylinder 16 permits an unattended operationof the device as well as the machining apparatus 1. In this case, anelectric motor, for example, may be used in place of the hydrauliccylinder 16 insofar as the cylinder can be thereby driven.

Since the housing 6 is hollow cylindrical, the contact ring 9 can beheld in place with good stability, and the presence of the bearing 7renders the contact ring 9 smoothly rotatable.

When the device is to be used for preventing the deflection of anelongated workpiece M of different outside diameter, the position of theengaging piece 23 is altered by rotating the stopper ring 19 relative tothe cylinder 18. The housing 8 is thereafter rotated about the supportshaft 12 to vary the angle of inclination of the rotational axis of thecontact ring 9 relative to the rotational axis of the contemplatedworkpiece M, whereby the workpiece M of different outside diameter canbe supported by the inner periphery of the first ring 9a and the innerperiphery of the second ring 9b.

FIGS. 5 to 8 show a second embodiment of the invention. Throughout thedrawings showing the first and second embodiments, like parts aredesignated by like reference numerals, and different features only willbe described.

The contact ring 9 of the second embodiment is not divided into twosegments but is in the form of a single member and is supported directlyby the bearing 7. It is simpler in cross sectional configuration thanthe ring of the first embodiment as seen in FIG. 6.

The means 17 for adjusting the angle of rotation of the housing 6 aboutthe support shaft 12 comprises a stopper ring 19 fixedly fitted aroundthe shaft 12 and made rotatable with the shaft 12. An engaging piece 23extends from the stopper ring 19 radially outwardly of the support shaft12. The mount bracket 13 has a support piece 24 projecting therefromtoward the housing 6 and having a screw rod 25 mounted thereon by a nut26 screwed on the rod.

When the housing 6 is rotated about the support shaft 12 as seen in FIG.7, the engaging piece 23 also rotates with the shaft 12 to come intocontact with the end of the screw rod 25, whereby the angle of rotationof the housing 6 is set to a specified angle. In the state of FIG. 7,the outer periphery of an elongated workpiece M having a given outsidediameter is supported by one end and the other end of the innerperiphery of the contact ring 9.

When an elongated workpiece M having a smaller diameter than theworkpiece M of FIG. 7 is to be prevented from deflection, the screw rod25 is rotated relative to the nut 26 and thereby shifted to adjust theposition of contact of the engaging piece 23 with the screw rod 25 asshown in FIG. 8. This varies the angle of rotation of the housing 6 foradjustment, altering the angle of inclination of the rotational axis ofthe contact ring 9 relative to the rotational axis of the workpiece M tobe handled, with the result that the workpiece M having a smallerdiameter than the one shown in FIG. 7 can be supported at its outerperiphery by the axially opposite ends of the inner periphery of thecontact ring 9.

When a plurality of deflection preventing devices 2 are used for asingle elongated workpiece M, an improved deflection preventing effectcan be achieved.

Although the foregoing embodiments are used for feeding the elongatedworkpiece M longitudinally thereof, this mode of application is notlimitative but the present invention is usable also for those which arenot moved longitudinally thereof.

The elongated workpiece to be handled by the present device is notlimited to one which is to be worked on by a machining apparatus. Thepresent invention is applicable to any material which needs to beprevented from deflection while rotating about its longitudinal axis.

INDUSTRIAL APPLICATION

The invention can be utilized for preventing deflection of elongatedmaterials rotating about their longitudinal axis.

What is claimed is:
 1. A device for preventing deflection of anelongated workpiece rotating about its longitudinal axis, comprising ahousing in the form of a hollow cylinder, and a contact ring rotatablymounted on the housing for receiving the elongated workpiece insertedtherethrough, the contact ring being rotatably fitted in the housing bya bearing, the housing being adjustably rotatable about a support shaft,the support shaft being perpendicular to the axis of rotation of thecontact ring, the angle of inclination of the rotational axis of theelongated workpiece relative to the axis of rotation of the contact ringbeing variable by the rotation of the housing about the support shaft,the outer periphery of the elongated workpiece being rotatablysupportable by the inner periphery of the contact ring at one axial endand at the other end thereof.
 2. A device as defined in claims 1,wherein the contact ring is made of a material other than the metal. 3.A device as defined in claim 2, wherein the contact ring comprises twodivided segments arranged side by side axially of the ring.
 4. A deviceas defined in claim 2, wherein the device has means for adjusting theangle of rotation of the housing 6 about the support shaft.
 5. A deviceas defined in claim 2, wherein the device has drive means for rotatingthe housing about the support shaft.
 6. A device as defined in claims 1,wherein the contact ring comprises two divided segments arranged side byside axially of the ring.
 7. A device as defined in claim 6, wherein thedevice has means for adjusting the angle of rotation of the housingabout the support shaft.
 8. A device as defined in claim 6, wherein thedevice has drive means for rotating the housing about the support shaft.9. A device as defined in claim 1, wherein the device has means foradjusting the angle of rotation of the housing about the support shaft.10. A device as defined in claim 9, wherein the device has drive meansfor rotating the housing about the support shaft.
 11. A device asdefined in claim 1, wherein the device has drive means for rotating thehousing about the support shaft.
 12. A device as defined in claim 1,wherein the contact ring comprises first and second rings at axiallyopposite ends thereof.
 13. A device as defined in claim 12, wherein eachof said first and second rings is provided with an annular cutout in oneend face.
 14. A device as defined in claim 13, wherein a contact portionis formed by the annular cutout at the inner periphery of the first andsecond rings of the contact ring; and wherein an annular spring isfitted in each annular cutout so as to extend around each contactportion.